Metallic capsule.



Nu. 666,723. Patented Jan. 29, l90l.

F. A. WILMDT. METALLIC CAPSULE.

(Application filud A r. 12, 1900.

(No' llodel.)

a INVENTOR S E S S E N H W NITE TATES iATENT Fries.

M ETALLIC CAPSULE.

SPECIFICATION forming part of Letters Patent No. 666,723, dated January 29, 1901.

Application filed April 12, 1900. Serial No. 12,597. (No model.)

To all whom it may concern.-

Be it known that I, FRANK A. WILMOT, a citizen of the United States,residing at Bridgeport, county of Fairfield, State of Connecticut, have invented a new and useful Metallic Capsule, of which the following is a specification.

My invention relates to metallic capsules, or, as they are commonly known to the trade, sparkletsz'. 8., small metallic reservoirs especially adapted for holding liquids and gases under high pressurefor example, a pressure of from eight hundred to one thousand pounds to the square inch; and my invention has for its object to provide a capsule of this character which shall be so construct-V ed as to render blowing out practically impossible, which shall render the use of rubber gaskets or packings of any kind unnecessary, which shall effect a savingin the cost of material in each capsule and without increase in the cost of manufacture, and which shall, moreover, effect a marked'saving in the labor of charging the capsules.

With these ends in view I have devised the novel metallic capsule of which the following description, in connection with the accompanying drawings, is a specification, reference characters being used to designate the several parts.

Figure l is a longitudinal section of one of my novel capsules closed as when charged and ready for shipment; Fig. 2, a similar view showing the cap in place and ready to be locked by the closing in of the upper end of the shell, the inner surface of the shell at the upper edge being roughened or corrugated; Fig. 3, a view similar to Fig. 2, with the exception that the outer surface of the dome-shaped cap is roughened or corrugated, the inner surface of the upper edge of the shell being left smooth; Fig. 4, an elevation of a dome-shaped cap corresponding with Fig. 2 detached; Fig. 5, an elevation of a dome-shaped cap corresponding with Fig. 3'

the shell is compressed upon it. This, however, I do not consider an essential feature of construction.

A denotes a metallic capsule made, for eX- ample, of mild steel and the neck B of which may or may not be reduced, as shown in the drawings. I

10 denotes a shoulder upon the inner side of the neck, which may or may not be inclined downward and backward from the front edge thereof, as clearly shown in Fig. 6. The inner surface of the neck above this shoulder may or may not be roughened or corrugated, as at 11.

C denotes a rounded domeshaped cap, which may be made, for example, of mild steel and whose edge lies in the plane of the curvature thereof,although, of course,the special design of the domet'. e., the height or flatness of the curve-is a matter of no importance so far as the principle of my inven-- ferential, it being of no special importance just how the neck or cap is roughened, although radial corrugations are preferably avoided.

In charging the capsules special machines are of course required, which, however, have nothing to do with my present invention, it being deemed sufficient for the purposes of this specification to say that the capsule is held firmly and the cap forced down upon the shoulder, which forms a seat for the edge thereof, the charge of liquid or of gas in the capsule being of course prevented from escaping, after which the cap is locked securely in place and leakage of the charge prevented by closing the upper edge of the neck down upon the dome-shaped cap, as is clearly shown in Fig. 1. In practice paraffin-wax or any other suitable material may be placed upon the closing-surface of either the neck or' the cap in order to make the seal of the contents additionally secure. This I do not consider essential, however, as in practice the neck is closed down so tightly upon the cap that whether or not either of the parts is corrugated or a sealing material is used a perfectlyt-ight joint is secured by the mechanical act of closing the neck down upon the cap.

Having thus described my invention, I claim--- 1. A metallic capsule having a neck pro-' vided with an internal shoulder and a domeshaped cap whose edge is in the plane of the curvature thereof and engages the shoulder, said cap being locked in place and the contents of the capsule prevented from escaping by closing the neck down upon the cap Without packing. 

